Adventures In Audiophilia

As those of you who follow this blog may remember, a few months ago I boxed up my Spatial Audio M4’s and shipped them back to Spatial in Utah in partial credit for an upgrade to the big sibling of the M4, the M3 Turbo S.

I have been writing this review for several months and I appreciate your being so patient during that time. While much of the delay had to do with the busyness of my work and family commitments, this review was also delayed because my experience with the Spatial M3’s took a major and unexpected left turn a couple of weeks ago. Here’s what happened…

Prologue: “Certainty”

I had originally planned to call this Prologue, “Amplifier Orthodoxy,” which is one of many audiophile orthodoxies that you encounter in online forum posts. You know what I’m talking about: people who believe that digital will never catch up to analogue, or that a speaker must use first order crossovers (or no crossover at all) to sound like real music. And in the universe of amplification, you find not only devotees of solid-state versus true believers in tube power, but there are also smaller rivalries within the two camps. For example, it’s easy to find folks in the solid-state tribe who swear by Class D amplifiers, versus those who swear at all Class D amps as cold and lifeless. And within the tube amplifier tribe, you’ll encounter battles between the folks who think that push-pull designs can be just dandy, shaking their heads in condescension at those who, fervent in their belief that no other topology is worthy of their time and money, swear by single-ended triode designs, .

I have been a member of the SET Tube Team ever since I heard how much better my old Reference 3A De Capo monitors sounded when driven by my Audio Note Kits “Kit 1,” compared to the Manley Mahi push-pull, mono-block amps that preceded it (and the Bel Canto S300, Class D amp that had come before it…) This SET “conversion” experience was itself the result of an online forum comment to the effect that “you haven’t really heard what the De Capo’s are capable of until you have heard them with a SET amp!!” So FOMO (Fear Of Missing Out) dictated that I had to try a SET amp.

Fast forwarding a year or so, I began to suspect that the De Capos weren’t nearly as efficient as I had thought. As a card carrying member of Team SET (not to mention cherishing my memories of the hours and hours I had invested in lovingly building that amp, resistor by resistor, capacitor by capacitor, with my own two hands), I was convinced that the Kit 1 was my “forever” amplifier. Thus, I was going to have to find speakers that were better suited to its capabilities, because that amp simply wasn’t going anywhere, ever. Out went the De Capo’s.

So the search for a good speaker match for my SET led me (with a detour into single driver speakers along the way) to the Spatial M4’s. At 93 dB efficiency, they seemed perfectly suited to my low-power, single-ended amp. And, it did turn out that the music made by the pairing of that amplifier with the M4’s was so dreamy, and so much more captivating than anything else I had ever heard in my listening room, that I was certain I was “done.”

Yes, I know: Famous Last Words.

This brings me to the revised title of this Prologue – “Certainty.” The title is a tribute to Leonard Kravitz (no, not that Lenny Kravitz), a professor of mine in grad school who used to like to say,

“Certainty doesn’t make you correct. Certainty makes you certain.”

In that spirit, consider the rest of this review an object lesson in what you may be missing out on if you become a little too certain of the truth of various, high-end audio orthodoxies…

Lend me an amp…

About a month ago, I began to question the validity of my emerging conclusions about the performance of the Spatial Hologram M3 Turbo S. After all, when you read a first-rate, professional speaker review, a thorough reviewer will typically test the speaker system with more than one amplifier (not to mention with different cables and other ancillary equipment). Yet all of my past speaker reviews had relied upon the only amp I own: the Audio Note Kits Kit 1 single-ended triode (SET) integrated that I built a number of years ago. I simply don’t have the budget to keep more than one amp, unused, sitting around waiting to be called into service when a new speaker comes through my listening room. Still, knowing from experience how much difference an amplifier change can make in the sound of an entire audio system, how could I make valid generalizations about the sound of the Spatial Hologram M3 Turbo S based upon driving them with only one amp, a low-power SET with its own distinctive sound?

Hmm. What if I could get someone to lend me a big, beefy, solid state amp for comparison?

I queried the Facebook group of one of our local audio clubs, to see if anyone could provide me with a high-powered , solid-state, integrated amp to try with the M3’s. Happily, a friendly fellow named Steve Truett offered to lend me his Krell KAV-400xi integrated amp (Stereophile review here). The Krell, which was released around 2004, pumps out 200 watts of class A/B power into 8 ohms, doubled to 400 watts into 4 ohms. In keeping with the Krell reputation for quality, it is also built like the proverbial tank.

Krell on the left, ANK Kit 1 on the right. (Do they make fun of each other when I’m not looking?)

I connected the Krell to my system, switched the power on, let it warm up, and then popped a CD into the drive and hit “Play.” I was not prepared for what happened next.

Compared to the Spatial’s performance powered by the 8 watts of my single ended triode amp, the Krell dramatically multiplied and strengthened every positive attribute of the Hologram M3 Turbo S. I was stunned! Here’s what I heard:

A much wider and deeper sound stage – huge, in fact – along with a more convincing “disappearing act,” the speakers not identifiable as the source of the music. For speakers considerably larger than the M4’s, this ability to vanish into the sound field is quite a feat!

A much more robust, tuneful and textured bass region.

More of the cohesiveness that I valued so highly in my M4’s and now M3’s. By this I mean that the musical performance makes sense and sounds right in such a way that your brain and body can relax with no extra mental effort required to interpret what you are hearing.

An increased sense of clarity and instrument separation, analogous to adjusting the focus on a projected image.

And, perhaps most impressive but hardest to verbalize, a perception that the presentation of the M3’s was more confident, more assured, than it had been with the little SET amp. By contrast, the SET left the speakers sounding “hesitant.”

I was so completely startled by the enhanced performance of the Hologram M3 Turbo S when driven by the big, solid-state amplifier that I gave Clayton Shaw of Spatial a call to try to figure out what had happened. Happily, Clayton enjoys speaking to his customers, and we spent the better part of half an hour on the phone as I picked his brains, trying to understand what could account for what I was hearing from the Krell amp. We discussed the pros and cons of tube amplifier output transformers and some other technicalities of amplifier design that frankly went a little over my non-engineer head. But my major take-aways were these:

Because the speakers in the Hologram line are quite sensitive (94 dB in the case of the M3) they can be driven to very satisfying volumes (and beyond) by just a handful of watts. However, the fact that a speaker is sensitive does not make it particularly easy for a “flea watt” amp to drive. You also have to factor in how the impedance of the speaker fluctuates throughout the range of its frequency response. A low powered, tube amplifier will generally want to see a pretty flat and high impedance load to sound its best. But the impedance curve of the M3 is not particularly flat and therefore not especially easy for a low powered amplifier to drive.

Clayton further explained to me that the output impedance of the amplifier is a key factor in the sonic synergy (or lack thereof) between an amplifier and speaker. Tube amplifiers tend to have a much higher output impedance than do solid-state models. And the sonic character of a tube amplifier with a relatively high output impedance will tend to be strongly affected by a speaker with a complex crossover and an impedance curve (and shifting phase angles) that vary significantly throughout the speaker’s frequency range. That’s one reason that single ended triode aficionados tend to gravitate toward single driver speakers with no electronic crossover. Single driver speakers present their own set of virtues and compromises, but at least they make the amplifier happy! It’s also a reason that Spatial recently introduced the M3 and M4 Triode Master models, with a higher, 16 ohm impedance and a more expensive compression driver that allows for a simpler crossover design. (The Triode Master’s dipole compression driver is supposed to further enhance the holographic qualities of the M3/M4 – leading me to the hope that I will get my hands on a pair of those one of these days…)

Anyway, it’s a testament to the quality parts and classic design of the Audio Note Kits “Kit 1” (the transformers are gigantic and the finished unit weighs nearly 50 pounds) that it’s capable of driving the Hologram M3 Turbo S so handily. That is, I was beyond happy with the sound of the Kit 1 and M3 pairing for many months.

But seeing how the performance of the M3 Turbo S skyrocketed with the more powerful amp convinced me that I needed to base my review of the M3 Turbo S on its synergy with the Krell rather than the ANK amp.

With that out of the way, here we go:

Specs

Although the M4 and the M3 Turbo S share a number of design themes (open baffle, controlled directivity, coaxially mounted compression driver, three drivers per side) there are several major differences:

The M3 is a substantially larger and (depending upon the size of the room) a more visually imposing speaker than the M4. It’s 6 inches taller and 3 inches wider than its smaller sibling. That may not sound like much, but when you’re used to the relatively petite silhouette of the M4, the M3’s larger size takes some getting accustomed to. Fortunately, the M3 shares the M4’s uncluttered, contemporary good looks and clean lines. The result of this unobtrusive design aesthetic is that even in a relatively small room like mine (around 16 x 13 feet with an 8 foot ceiling) the M3 doesn’t visually dominate the entire room.

The M3’s larger baffle accommodates some significantly larger drivers. Its two mid-bass drivers are 15″ in diameter as opposed to 12″ on the M4. This helps to account for the extra 13 Hz of low end extension (±3 db) offered by the M3.

The back of the upper driver complement, showing the basket of the mid-bass unit and the (sealed) rear of the coaxially mounted compression driver.The rear of the lower mid-bass driver.

I should note that the M4 that I traded in for my M3 Turbo S was a bit of a one-off hybrid within the Hologram line (as the line existed about 18 months ago, when Spatial offered Standard, Turbo and Turbo S models). It had a lower end titanium compression driver (lacking the special diaphragm stiffening treatment that’s standard on all current S models) and the binding posts of the “Standard” model, but with the better crossover parts of the Turbo and Turbo S models. Keep this in mind when I make comparisons between the M4 and M3 Turbo S.

Because I know you love them… Unboxing Photos!

The clever packing scheme of the M3 Turbo S is identical to that of the M4, except that it’s a much heavier and larger shipping carton. Unpacking the smaller M4 can easily be accomplished alone by a person of my height (about 5′ 7″) and average strength. I also managed to unpack the M3 Turbo S cartons by myself, although there were times when I’d have felt more at ease with another person standing by to help me wrangle those bigger boxes. Still, it’s not an unduly difficult job for one person.

Here’s the unboxing procedure:

This is the top flap of one of the cartons. And here’s a photo showing both cartons in front of my equipment cabinet, to give you some idea of how big those cartons are.

You begin the unpacking process by slitting the packing tape on the top of the carton and carefully turning the box upside down…

… and then lifting the carton upward and off of the M3’s packing materials. The box is tall enough that this was a bit of a challenge in my listening room, which has your typical 8 foot high ceiling. Still, with a little shimmying action to avoid the box hitting the ceiling, I was successful:

Note in the picture above that the M3’s come sheathed in two layers of protective plastic: an outer bag of heavy poly material, and multiple layers of plastic cling wrap to protect the painted finish on the baffle. (This seems like a good time to mention that the M3 is available at no extra charge in matte finishes of red, black and white!)

So now, with the speaker upside down, you’ll notice a cutout in the foam end cap that houses the speaker legs, feet and various accessories:

And here are the contents:

Above you’ll see the heavy, painted metal support legs, wrapped in protective foam sheeting, along with two baggies of screw-in feet: on the left, flat plastic feet for hardwood floors like mine, and on the right, spikes for carpeted floors. And if you look carefully at the bottom of the cut-out, on the right, you’ll see an Allen (hex) wrench for bolting the legs on to the bottom of the speaker baffles.

(Above, a better shot of the two kinds of feet.)

Opening the outer poly bag and peeling off the end strips of cling wrap, there’s more foam sheeting to protect the edges and corners of the baffle from shipping damage. This shot also gives you a nice glimpse of the fancy binding posts.

Remove the protective sheeting and you’ll find precisely sized channels and threaded sleeves cut into the bottom of each speaker baffle. This makes attaching the legs to the baffles simplicity itself:

And we’re almost there:

Here is one speaker, finally flipped right side up, still wrapped in protective cling wrap.

And here is the very final step of unpacking, about to remove the uppermost band of plastic wrap as well as the foam protective end cap.

At last, here they are, in position:

Digression #1: My Deeply Problematic Listening Room

As I’ve alluded to in past posts, my listening room is far from ideal. It doubles as a guest bedroom, is somewhat small and oddly shaped and houses leftover furniture from some office space that my wife used to lease. Because of its size, shape and multipurpose nature, there are significant limitations on how my speakers (and the rest of my equipment) can be positioned. For example, it’s well-known that having an equipment rack in between your speakers is far from ideal. Musically, it creates unwanted reflections that can mess up imaging and tonality. Visually, it distracts from the sought-after illusion that the performers are magically occupying the empty space between and around your speakers. Furthermore, the room features bare, reflective hardwood floors (because the people I live with suffer from allergies that are exacerbated by the crud that tends to hide in carpet fibers, no matter how often you vacuum them). This means that, as you can see in the picture above, when I listen to music, I spread out on the floor a comforter that otherwise covers the daybed that serves as my listening “chair,” which damps down at least some of the sonically deleterious room reflections that otherwise bounce off those varnished floors. I’ll explain in just a moment why I am detailing all of this at this point in the review, but first let me provide some photos of the room so you can get an idea just what I’m dealing with:

The right channel speaker, which is about 32 inches from the wall behind it and less than 2 feet from the side wall. This has proven to be about as “far into the room” as I can get them without compromising the room’s ability to be used for anything but the stereo.Rotating clockwise about 90°, you can see the right wall of the room, including the fact that a large ottoman sits along that wall, and is situated off to the right and about 4 feet from the right channel speaker baffle. Although this furniture does not obscure the sonic “line of sight” from the speaker baffle to my listing position, I’d imagine that it’s not doing my system any favors, either! Also, I should note that the window shade is pulled up in that shot in order to get better lighting for the photograph, but I have the shades pulled down whenever I listen, to provide at least some damping of unwanted reflections.So, we rotate clockwise another 90°. The room was embarrassingly messy when I took these quick photos, but there you see the daybed on which I sit when I listen to music. It is substantially taller than your average chair or sofa. The “niche” into which the daybed has been set is there in case we ever wanted to put closet doors in front of it and turn it into a real bedroom closet. But in the meantime, it means that my head is within a couple of feet of the wall behind me, which probably creates other undesirable reflections.Rotating clockwise about 45°, you can see the door into the room.Again rotating clockwise about 90°, here is the left-hand channel. It also sits around 32 inches from the wall behind it and you’ll see that the small sofa that goes with the ottoman on the opposite wall is situated just a couple of feet to the left of the speaker.

Here’s why I’m showing you my listening environment: I want to give you context for the sonic impressions that follow.

It’s one thing to get a pair of speakers to sound great in a properly treated, purpose-built home listening room or dealer showroom. It’s quite another to get exceptional performance in an acoustically compromised home listening environment that must serve multiple purposes. (Do any of you have a similarly compromised listening room? I bet you do!)

That said, the fact that the M3 Turbo S sounds as wonderful as it does in such a crummy listening room is a testament, in part, to the success of its controlled directivity design. Each speaker is designed to limit its dispersion to a rather narrow, 80° out front. This substantially reduces room interactions, especially early reflections that would muddy and confuse the sound. Again, the proof is in the listening, and I can vouch from experience that this controlled directivity business really works. I think you can validly assume that however great the M3’s sound in my room, they’d sound that much better in a more flexible, properly treated, single-purpose listening room.

Digression #2: A Few Words About Break-In

If you Google “speaker break-in,” you will find plenty of articles and audio forum posts debating whether or not the sound of a speaker changes from “fresh out of the box” as an increasing number of hours of playtime are accumulated. On one side of the argument are those who believe that speaker break in is “a thing.” On the other side of the debate are people who believe that speaker burn in is really “brain burn in,” i.e., your brain-ear system getting used to the speakers’ sound. (If you really want to go down that rabbit hole, you can find similar articles – and debates – about cables and electronics…)

In my experience, loudspeakers do break in over time, although the amount and nature of the change in the speaker’s sound will vary significantly from model to model. If you’re interested in learning more about why this might be the case, I’d recommend looking at this article and this article from the website of speaker kit supplier GR Research. And, perhaps more to the point for this review, speaker driver manufacturer Eminence, which supplies some of the raw drivers for the Spatial Hologram line, affirms in this article that speaker break in is a real, measurable phenomenon.

When I was first considering the M4 a couple of years ago, Clayton Shaw of Spatial told me that no speaker sounds its best fresh out of the box and that a certain amount of time warming up and settling in from shipping is required before the speakers begin to reveal their true nature. The M3 manual says, “At least 24 hours of run-in are required in order to make informed decisions about placement through listening. Bass will fill out and deepen, treble will smooth out and soundstage open up.” The manual then suggests letting the speakers run in for a few more weeks and then tweaking the positioning further.

Here’s my experience.

Although the M3’s never sounded “bad,” I can affirm what Clayton had told me earlier: straight out of the box you’re not going to hear anything close to what a well broken in pair sounds like. My M3’s sounded somewhat undistinguished when I first fired them up – a bit closed in and congested, without the expansive soundstage I’d come to value in the M4’s.

After about 5 hours, and then again around 10 hours, the speakers began to loosen up and I started to smile. The treble region smoothed out and developed more “air,” and the whole presentation became more flowing and relaxed – more musical. I ran them during the day while I was at work at good but not excessive volume levels, using some tracks that had enough drums and percussion to loosen up the suspension on those big drivers.

Taking the advice of the User Manual, at around 24 hours I adjusted the positioning of the M3’s, bringing them a couple of inches further out into the room and decreasing the angle of toe-in just a bit. I was rewarded with a more convincing “disappearing act,”with the M3’s less identifiable as the source of the music, as well as a wider soundstage, often extending well beyond the outside edges of the speaker baffles. I think I did a bit more tweaking of the speakers’ placement about a month later and they’ve remained in the same place ever since.

Since the finalization of their placement, I have continued to be regularly surprised (and delighted) by the continued evolution of their sound. The M3’s have become more open sounding and effortlessly dynamic. Instrumental tonality has become more startlingly realistic. The upper end has continued to smooth out and open up, adding inner detail and instrument separation without harshness. The bass and mid-bass have both deepened and become more tuneful – that is, percussion and electric and acoustic bass lines have more “thump” and power, but musical pitch in that region is much better defined. The soundstage has continued to bloom and become more expansive and more three-dimensional.

As of this writing, I have something in the neighborhood of 150 hours on the M3’s, and they have not stopped improving. Keep that in mind as you read what follows!

And now, the moment you’ve really been waiting for:

Listening Impressions – Down Low

When I started listening critically to the M3’s after the initial break-in period, I’ll confess that the first thing I focused on was the low end. How would those four big, 15-inch drivers deliver the bass goods in comparison to the smaller mid-woofers of the M4? Did I hear more low end energy and slam? Sure. More presence and power approaching the bottom octave? Certainly. (And I should note that the bottom end in particular has continued to open up even beyond 100 hours of play time.)

But to my surprise, the thing that really stopped me in my tracks as I explored the M3’s was a huge leap in bottom end control, texture, pitch, air and decay. To put it another way, the low end of the M3’s, like that of their smaller siblings, will move plenty of air and pressurize a room quite impressively. But it’s the nuance of that low end that really shines – it’s never just undifferentiated “BOOM” way down there – it’s always music.

To illustrate this, I’ll once again turn to one of my reference CD’s, the dramatic orchestral soundtrack to the classic anime film, Princess Mononoke. Its overture opens with two explosive “whacks” on some sort of huge, Japanese drum. And the first time I heard these on the M3 Turbo S, I was startled by something I’d never heard on the M4’s – a decay or reverb of the initial drum hit that seemed to go on forever, echoing off the walls of the venue in which it was recorded. It made me wish my CD player could decode the HDCD format in which this CD is recorded. Who knows what else is hiding in those 1’s and 0’s that I’d never heard before?

My teenage daughter and I are both huge fans of the New Zealand born singer known as Lorde, whose latest album, Melodrama, recently hit the streets. It is a much more elaborately arranged affair than the wonderful, but very melodically and instrumentally spare arrangements on Pure Heroine, her breakout CD from several years ago. Listening to Melodrama for the first time through the M3’s, I was struck by many things, but in this context, discussing the low end, the amount of air that those big, 15 inch drivers can move became strikingly apparent, giving chest-thumping power to the fat, synthesized percussion that often dominates the more danceable tracks on this new CD. The M4’s could suggest this kind of room energizing power, but the M3 actually delivers it. I should also say that the huge, sampled bass drums from her biggest hit so far, Royals from the album Pure Heroine, have a percussive authority and tonal refinement that I’d never heard before I paired the Krell amp with the M3’s. You don’t just get the “thud,” you also get the initial impact that makes this sound like a drum (albeit a sampled one).

Here’s yet another example of what the M3’s low end is like. Side 1 of Joe Jackson’s classic Night and Day LP is a percussion fest, awash in drums, timbales, glockenspiels and more. Listening to the opening track, Another World, I was positively startled by the realism of percussionist Sue Hadjopolous’ tympani strikes on the downbeat of each opening bar. The leading edge impact, deep tone and reverb around the instrument were reproduced with an authority and rightness that left me grinning! Just beautiful.

A bit further on in this review, in the section on imaging and sound staging, I’m going to make reference to Norah Jones’ Come Away with Me CD. But in the current exploration of the bass capabilities of the M3 Turbo S, let me call attention to one of my favorite tracks on that CD, Norah’s reworking of Cold, Cold Heart by Hank Williams. The cut begins with nothing but an ostinato figure played on the upright, string bass. I have listened to this track countless times, and was completely surprised by the way in which the M3 Turbo S, now driven by stable, solid-state power, confidently rendered not only the pitch and “pluck” of each acoustic bass note, but also conjured an image of the resonant, wooden body of the instrument. It was one of those “I had no idea that was on the recording” moments.

Additionally, a few years ago I made it to the California Audio Show outside of San Francisco. Reference Recordings had a booth there, and I picked up a couple of two of their CDs, including a sampler called Jazz Kaleidoscope. Although you could have a lively debate about whether the track O Vazio by the Jim Brock Ensemble is truly “jazz” at all (a debate that I will not touch with the proverbial 10 foot pole) it is, like the rest of the album, unbelievably well recorded (as you would expect from Reference Recordings). Near the beginning of this composition, there is some sort of subterranean (synthesizer?) tone that is played twice, and the M3 Turbo S (with the right amplification) nails the astoundingly deep rumble of that tone to a degree that’s almost unnerving. Very cool.

I thought it would be cool to try to ascertain (without access to testing equipment) just how low the M3 Turbo S can play in my rig. To try to answer this question, we turn to another piece of music that I love, both for its inherent gorgeousness and also for its ability to suss out the low end of a speaker system: Negative Girl from Steely Dan’s Grammy-winning 2000 CD, Two Against Nature. As I have pointed out in other reviews, the opening bars of this delicious, jazzy track feature electric bassist Tom Barney playing a syncopated figure on a five string electric bass. Each repetition of the figure is in a lower register until, the last time it is played, the lowest notes of the figure are extremely low. In an attempt to leaarn exactly howlow those notes are, posted a query on the Dandom.com Facebook fan page.

What I learned from one of the group’s very helpful (musician) members is that the lowest of those electric bass notes is a low C# (AKA D flat) which sounds three frets lower than the usual low E of a four string bass. It would have a frequency of around 34.6 Hz. Therefore, given that the frequency response of the M3 is rated, in room, down to 32 Hz (± 3 Hz), the lowest electric bass notes at the beginning of Negative Girl would just be scraping the lower limits of M3, although the higher harmonics of that note (multiples of 34.6) should still give some presence to the note. Here, the extra muscle of the Krell amp made itself felt: with the exception of that lowest C-sharp, every other note of the bass figure was reproduced with a presence and power not revealed when the M3 was driven by my SET tube amp. With the Krell amp, the C-sharp was much more palpable, but at a slightly lower volume than the rest of the electric bass notes. Should I put much stock in this? Probably not. I’ve never heard any speaker play that note as loudly as the rest of that bass line (the closest has been my KEF-M200 in ear monitors), leaving me to suspect that the reduced volume of that note simply reflects how the track is mixed. For what it’s worth, my whole Negative Girl “test” suggests that the published 32 Hz low end spec of the M3 Turbo S is a realistic one.

Listening Impressions – Mids

As is often said, most music “lives in the midrange,” which explains why audio gear enthusiasts’ record collections tend to contain a lot of recordings of female vocals. The theory is that if a system (in this case, a speaker) can nail the sound of the human voice, everything else is comparatively easy. This can make it somewhat tricky to choose music to reference in a review. On the one hand, I try to avoid making reference to obscure, “audiophile specialty music” that my reader is unlikely to have ever heard, much less possess in their personal library. (Here I must confess that from time to time over the years I have been suckered into buying one of these “audiophile” discs, filled with beautifully recorded music that I don’t particularly enjoy but might play in order to show off my rig when a friend comes over.) At the other extreme, I also try to avoid referencing overplayed but sonically brilliant female vocal recordings – again, the kind of stuff that you can’t get away from at audio shows.

Pardon me, therefore, as I violate that rule a bit with a reference to Jennifer Warnes’ iconic recording of Leonard Cohen songs entitled Famous Blue Raincoat. I own the twentieth anniversary, Cisco gold CD remastering of this album. Except for some rough, etched edges around the singer’s voice that the Cisco remaster seems to have inflicted on the original recording, the engineering on this record is quite pristine: The Stuff of Legend, as they say. But the Spatial M3 Turbo S, especially with the Krell amplifier, works some kind of magic with this album. It elevates the experience of listening to this CD from hearing a “well recorded record of a good singer” to something genuinely moving and beautiful. Her voice is rendered as a flesh and blood, human instrument, full of nuance, subtle phrasing and emotion.

I am especially drawn to Famous Blue Raincoat, the title track. As soon as Jennifer begins to sing the opening words, “It’s four in the morning…” I was hooked and couldn’t stop listening. And even before that moment, when the bluesy tenor sax comes in, it was very close to like having a saxophone player in the room with me.

When a stereo system brings you this close to the emotional core, to the artistry of a fine performance, the gear itself becomes irrelevant and it’s all about connecting with the music. It’s quite sublime.

The same can be said for many of the wonderful tracks in the 2-LP set, Todd Rundgren Anthology (1968-1975). I am particularly sentimental about the song Be Nice to Me, as it figured into some tender moments in my wife’s and my early courtship. It’s a beautiful song, and Todd Rundgren’s voice is just THERE, suspended between the speakers, reedy and lovely.

Listening Impressions – Highs

I will not dwell at too great a length on the high-frequency presentation of the M3 Turbo S, except to say that it is sweet, delicate, airy and extended. More than any of that, though, I appreciate the fact that the high end of these speakers never feels exaggerated or tipped up in the name of creating a fake impression of being “revealing,” an illusion that might be seductive in a dealer showroom but will get tiring and strident pretty quickly at home.

To put it another way, this is a speaker whose high end “does no harm,” in the sense of not making “hot” or bright recordings sound even worse. In fact (surprisingly, even more so with the solid-state amplifier) the M3 Turbo S seems to tame the over-hyped or hot treble equalization on some pop recordings.

For example, do you remember the sound of many of Hall and Oates’ later hit records – the envelope of thin, high-frequency “fuzz” that the engineer slathered all over their vocals? For some reason, through the M3 Turbo S, you are aware of what the engineer chose to do but it never gets fleeing-the-room obnoxious, the way it can on many other highly resolving speakers. Again, I don’t think this is because the presentation of the M3 Turbo S is rolled off or veiled, but rather, because it is fairly honest and flat. And so, the vocals on Rich Girl or Kiss On My List are sharp-edged and hot, yet not obnoxious or offensive. I consider this a good thing.

Listening Impressions – Tone

In my original review of the M4’s, I described those speakers as being “masters of tone.” I also said that I understood for the first time what some audiophiles mean when they say that no matter how good the imaging, “PRAT” or sound staging of a speaker might be, if instruments and voices don’t sound like what they are in real life, what good are any of those other qualities? As you would expect, the M3’s are also masters of tone, but in an even more striking way than the M4’s – which is really saying something. So, well recorded electric guitars sound exactly like electric guitars, brass instruments like trumpets and trombones have the bite and impact of the real thing, saxophones are re-created in all their breathy, woodwind glory and, well, you get the picture.

Now, when I make these comparisons between the M3 Turbo S and my original M4’s, it’s hard to say exactly how much of the improvement is due to the better crossover parts and larger drivers, and how much stems from the fact that my M4’s did not have that better titanium nitride coated compression driver that is now standard on the M4 (and, of course, on the M3 Turbo S, as well). But whatever the reason, the improvement is not subtle.

Also, under the “tone” category, I want to give special mention to the transient speed that the M4 Turbo S exhibits. You hear it especially on stringed instruments like acoustic guitars and on percussion instruments like snare drums. Take, for example, another audiophile classic rock favorite, Hell Freezes Over, the hybrid studio/live reunion album by The Eagles. The plucking of the guitar strings, whether folk/steel strings or classical/nylon-strings, has a realness and convincing, percussive quality that can be pretty spine tingling on a track like Hotel California. The same can be said for the sound of the snare drum brushwork on the breakout hit Don’t Know Why from Norah Jones’ Come Away with Me CD. Again, I could give many more examples of this but you get the idea…

Listening Impressions – Imaging and Sound Stage

Okay, here comes the fun part! As I have confessed a number of times in prior posts, I love sound staging and imaging effects. To repeat something I’ve said previously, I know that lots of people dismiss this aspect of home audio: “You don’t experience location-specific imaging at a live concert, so why should you care about it when you’re listening to music at home?” I look at it a different way: I want to hear everything that the recording engineer intended. So, whether it’s a live recording of acoustic instruments or a heavily multi-tracked studio album, if the producer and recording engineer worked hard to provide an expansive soundstage and pinpoint imaging in the recording, then I want to hear that in all its glory. To cite an extreme but well known example, if I am listening to The Dark Side of the Moon and I don’t perceive phantom sounds zooming at my head from every direction, if some of the tracks aren’t borderline frightening, then I know the system isn’t giving me engineer Alan Parsons’ brilliant vision with all its fun house craziness intact.

I don’t know why I am so taken with this aspect of home audio. Maybe it goes back to the 1980s, when I actually owned a Carver C-9 Sonic Hologram Generator, a slim black box that created (sometimes appropriate, sometimes ridiculous) three-dimensional and surround sound effects from two channel stereo by selectively injecting out of phase signals into the mix. I haven’t actually used my C-9 in decades, but I still love a palpable, three-dimensional presentation when that’s what’s embedded in the recording. On the other hand, I don’t want big, spacey effects slathered all over a recording when it’s not actually part of the artist’s intent, as I have experienced with some omnidirectional speaker designs.

Simply put, the Spatial M3 Turbo S amply lives up to its moniker, “Hologram.” I have never experienced such a broad, spacious, three-dimensional presentation as I have with this speaker in combination with that solid state amplifier. This was a shock to me, considering the common wisdom that tube amplifiers trounce solid-state amplifiers when it comes to a three-dimensional presentation of the music.

I’ve already made reference earlier in this review to Norah Jones’ Come Away with Me CD. Rendered by the M3 Turbo S, the speakers themselves and the walls of my listening room completely dissolve and it’s just me, Norah Jones and her wonderful backup band. Individual instruments float in space and you are bathed in the singer’s warm, smoky delivery. The title track, in particular, sounds sublimely ethereal and expansive through the M3 Turbo S: guitars ring, cymbals shimmer and decay, the piano sounds strikingly real.

The M3 Turbo S can also do something extremely special with background singers in some rock and pop recordings. Take, for example, Lou Reed’s iconic take on life on the edge in New York City, Walk on the Wild Side. When Reed semi-sings, “… and the colored girls go…” and slowly, the background singers’ voices seem to fade in from some distant place until all the reverb is gone and their “doo, de-doo” is completely echo-less and closely miked, it’s as if those singers are sitting on the couch, on either side of you, singing right into your ears and somehow filling the rest of the room, as well. I defy anyone not to grin hearing that song through these speakers.

Finally, I’ll close out this section of the review by mentioning the almost entirely instrumental track True Companion from Steely Dan gold, Expanded Edition. This selection, from the soundtrack of the animated science fiction film, Heavy Metal, is extraordinarily well recorded, three dimensional and flat out trippy. The M3 Turbo S does an exemplary job of completely vanishing into an enormous sound field, especially when the swirling keyboards enter in the second measure: your room vanishes and you are aboard an intergalactic cruiser as a chorus of Donald Fagens croons:

Crewmen of the True Companion

I can see you’re tired of action

In this everlasting twilight

Home is just a sad abstraction

In the immortal words of Keanu Reaves, “Whoah.” It has to be heard to be believed.

Compared to the M4

Comparing the current M3 Turbo S to the M4 that I previously owned is a bit tricky because, as I noted earlier, my M4’s used the discontinued, base model compression driver in an entry-level M4 configuration that is no longer offered by Spatial. Therefore, given that the compression driver that covers most of the audio band is different than the one currently used in the M4, I’m not giving you an exact, “apples to apples” comparison.

With that disclaimer, I will say this: I would characterize the presentation of the M3 Turbo S as bigger, more dynamic, more open and more “relaxed” than the M4. The two speaker models certainly share the same sonic DNA: lovely midrange, unfettered, open presentation, tremendous imaging and soundstage prowess… But the M3 simply “goes bigger” with a perceived ease and openness that the M4 doesn’t quite manage. Again, it’s important to remember that so much of this depends upon associated equipment and, perhaps more than anything else, the room in which your system is situated.

Speaking of “the room:” Is the M3 Turbo S “too big” for the room I have them in? I’ve spent a lot of time thinking about this, both before and since my upgrade from the M4 and I think my answer is “no.” Again, because of that controlled directivity design principle and the way that open-baffle bass loads the room, the M3 Turbo S does remarkably well in my highly compromised listening space. My only caveat is that without the ultimate flexibility to position the speakers anywhere I want, I suspect that I’m still not getting everything the M3 Turbo S has to offer. Specifically, I bet I could get a deeper soundstage and even better-defined bass response if I could get the darn things further out into my room and away from the front and side walls. So, would YOU do better in your listing space with the M3 or the M4? For this, I have one, foolproof piece of advice: call Spatial and talk to Clayton. He is a straight shooter and will not steer you wrong.

In the process, I have also learned an important lesson: it pays to take the various audio component design orthodoxies with a large grain of salt. “Certainty doesn’t make you correct. Certainty makes you certain.” Take this from a guy who thought he would never look at another solid-state amp – that is, until he realized that he had never heard what his speakers could really do given the right match.

Thank you for reading this gargantuan post. As always, I love reading and responding to your comments.

Until next time, show the world some kindness and respect and enjoy your music!

Great Review thanks
Just what we needed
My friend has a pair of the M2 Turbos he spent 2700 bucks on
He has been trying to upload them for a while now at 795.
Perhaps now, with this great review, he can finally sell them upgrade to a pair of 1450 Vandersteens1Cis

Glad to be of service! 😉
I remember the M2 Turbo’s – an early iteration. They must be a few years old, now.
My very first “real high end” speakers were the original Vandy 2C. Not winning any beauty contest but a classic and much-loved design for sure.
Thanks for posting!

nice review Rebbi. I have M2 Turbos and enjoy them even though I have a less than perfect listening room myself. Not sure if you remember me but I bought some LSA monitors from you a few years back. Great to see you’re still in the game :). Lance

Thank you so much for the kind comments! I write these reviews to share what I’ve learned with fellow audiophiles and music lovers, so I hope this helps you to make a choice that brings you joy. Thanks again!

True confessions… I have a Carver Sonic Hologram unit in my system, along with a Primaluna Dialogue 1 tube amp, and I can tell you, the M3s are so perfectly suited to the Carver unit. The soundstage is unreal, but not out of control or phony. No speakers every sounded better with the Sonic Hologram Generator. The M3s generate a wonderful sound stage on their own (my vinyl loop doesn’t go through the Carver), but when the Carver is added to certain songs, well… you just have to experience it.

Dear Wes, that is so cool!
I’ve never met anyone else who actually had a Carver Sonic Hologram processor. I actually tried to sell mine to somebody on Audiogon, I think, a number of years ago but when they got it they said they couldn’t get it to function properly. So they returned it to me (missing the printed manual – I was pretty ticked off) and I refunded their money. I haven’t had the chance to use it since because I haven’t had an amplifier with a tape loop or pre-amp out connections for a long, long time. I remember that with some music (and I think this is back in the day when I had Vandersteen’s – the 2C) the processor did some really amazing and pleasing stuff. I can’t remember any specific examples right now, except that the effect could be most dramatic when instruments or vocals were panned all the way to the right or the left channel. Then, sometimes it got silly, like listening to orchestral tracks and feeling like I was sitting in the middle of the violin section, or like somebody was playing trombone off to the side in the bathroom! 🙂
Anyway, big nostalgia trip for me in your post. Thanks for sharing!

Believe or not, 20+ years ago, I had a carver c1 preamp which had a sonic hologram circuit included that definitely added some ambiance and depth and could be turned on or off as desired. My understanding is that it performed some form of crosstalk cancellation similar to what goldenear does with its sound bars. My current system/room does a far better job than the carver ever did… but I have to say that the goldenear sound bar is amazing for only being 50″ wide.

Rebbi, Thanks for the great review! I had had the good fortune to be in Salt Lake in September so I called Clayton and asked to stop by. I was/still am interested in upgrading from my current loudspeakers (also made in Utah) and the open baffle idea along with made in America appealed to me. Clayton’s facility was a combination office, small warehouse, assembly operation and listening area. The listening area was by no means ideal but I got to hear the M3 turbos and they were excellent, even in a less than ideal environment…The had a wide soundstage, male and female vocals exhibted no sibalance, tonality was great and they had the “you are hearing it live” vs listening to someone’s stereo type sound. They sounded realy good played soft or loud; and man could they play loud without a hint of bite!! I had made up my mind to buy them but became concerned that their sonic center is pretty low…maybe 31″ from the floor …and my listening position is 12′ back and 36″ high. Can you make some more comments about the rectangular dimensions of your room…how far back your listening position is….whether the low center is an issue in any respect…how wide is the soundstage beyond the speakers. Also, Clayton was a perfect host and applied zero pressure whatsoever and answered every question I had. And I have to say that I think the M4s and M3s look good in all the photographs you see but they look even better in person.

Hello, Ron,
Thank you so much for taking the time to post. I am happy to provide some measurements for you.
At its widest point (that is, from the wall behind the speakers to the wall in back of my head) the room is about 13.5 feet wide, and around 16 feet from end to end on the long wall, although not all of that space is usable because of the love seat on the left. My ears are around 9 feet from the front plane of the speakers. In terms of the space between the speakers, the inside edges of the speakers are 68 inches apart, and the outer corner of each speaker (the one further from the wall because they are toed in slightly) is 28 inches from the wall in back of them.
In terms of the sonic center of the speakers, conventional wisdom (whatever that means) with most speakers is that you want your ear to be more or less level with the tweeter. You’d have to ask Clayton (and it would be a good question) where he thinks the year should be in relation to the drivers. In terms of seating height, the upper surface of the mattress of the daybed that I sit on when I listen is almost exactly 24 inches from the floor. I don’t know how much that actually tells you, though, since where a person’s ears are in relation to that is going to depend upon your own height and body proportions!
The soundstage in relation to the outside edges of the speakers varies from track to track. On some music, most of the action is taking place suspended between (and behind, and sometimes out in front of) the speakers themselves. On some tracks, depending upon how they are recorded, the soundstage is huge and extends well beyond the left and right edges of the speakers. (In the review, I tried to give some examples of music that exhibits a particularly wide presentation in this way.) As I said, I like the fact that the Hologram’s do not impose an unnaturally wide soundstage of their own. They can do that trick, big time, but it just depends upon the music itself. In any event, I have not found the height of the drivers to be an issue in my set up. Again (not to be a broken record) I’d check with Clayton to see if he thinks your set up would be a problem. Ultimately, it’s very hard to know in advance how this will play out – you just have to hear them in your rig and in your room. That’s why it’s good that he gives you a sixty day trial period see how you like them.
Sorry for the meandering response – I hope this helps!

I assume your comparison of the M3 and M4 were both done with the Krell instead of the M4 with the ACT. I am also not convinced about speaker break-in in spite of Eminence simply saying it’s true. After all you would not wait 150 days for your TV or Ferrari to break in and if it were that real I imagine manufacturers would simply have a break-in room to ensure the best arriving sound possible. My last concern is Spatial’s newest speaker dropping the M3/4 tweeter and adopting the AMT and it makes me think there are going to be significant evolution at Spatial going forward. And all this is actually from someone who loves what Spatial is doing.

Hi, Henry!
Thank you for the thoughtful post.
You make a good point about the limits of my comparison between the M4 and the M3, since I did not have access to the solid-state amplifier when I owned the M4‘s. It would be interesting to see how much/if the gap in performance between the two models narrowed if they had both been driven with the Krell amp.
As per speaker break in, it’s precisely because some people buy the idea and some people don’t that I included that section in the review. In my experience, it’s a real phenomenon, but, as I said, how noticeable it is has, in my experience, varied depending upon the speaker and the underlying technology. For example, I once owned a single driver loudspeaker that was supposed to improve with break-in, but no matter how many hundreds of hours I ran it, I never found the less than satisfactory aspects of its performance to improve. As for your question about why speaker manufacturers don’t break them in at the factory, some manufacturers do. Years ago, for example, when I owned Merlin monitors, the designer, the late Bobby Palkovic, used to run all his speakers on a break-in rig for, I think, 48 hours before he shipped them. but as you would expect, this kind of pretreating at the factory slows down the production of the speakers and also increases the cost. And I guess that’s why most speaker manufacturers don’t go to the trouble. Anyway, I’m just reporting my own experience.
Yes, the addition of the Air Motion Tweeter in the X series models is supposed to constitute quite a major jump in performance. Whether the use of that tweeter will trickle down to more affordable models is anyone’s guess. But I do trust that Clayton is always cooking up new ideas, so I look forward to seeing whether that (or something else interesting) occurs.
Thanks again for posting.

I’d like to make two comments. Clayton told me that the M3 & M4 sound virtually the same with the difference being low end extension. The M4 is for smaller rooms that would be overloaded with the 15″ transducers.

As for the M2 AMT, if you look at the size of the AMT unit in this link (photo at the bottom of the page) http://www.audiocircle.com/index.php?topic=153006.0 , its a big unit and probably has to be in order to cross over below 1000hz. I would not be shocked if they cost $1000 a pair…which makes me think its unlikely that they can make it to the M3/M4 based on cost alone.

Upon Further Reflection…..The whole AMT thing tweaked my interest as I’ve always really liked the sparkle and dimensionality that well done AMTs provide. Check out this link http://www.pureaudioproject.com/trio10-open-baffle-speakers/ As it turns out, Heil, Mundorf and Beyma all make AMTs that cross pretty low and might fill the bill for Clayton’s designs/voicing… although probably for an upcharge. I could see Spatial offer an M3 with different tweeter options at different price points. One downside to that though…and you will experience it with the pure audio website…there are so many options that it is easy to get confused/paralyzed as to what option might be most to your liking. There is a lot to be said for “make it musical and keep it simple”.

Interesting, thanks. You know, I’ve always been sort of interested in the Pure Audio Project products. In fact, if I had more disposable income, I would buy one of them. But, as you say, there’s almost too much choice there and it’s hard to know what the best choice would be. On the other hand, I love the do it yourself aspect of it all. Thanks, as always, for posting!